browser: handle launcher paths that contain spaces

pkg/browser/browser.go

@@ -61,15 +61,11 @@ func (b *Browser) browse(url string, env []string) error {
 		return cliBrowser.OpenURL(url)
 	}
 
-	launcherArgs, err := shlex.Split(b.launcher)
+	launcherExe, launcherArgs, err := splitLauncher(b.launcher)
 	if err != nil {
 		return err
 	}
-	launcherExe, err := safeexec.LookPath(launcherArgs[0])
-	if err != nil {
-		return err
-	}
-	args := append(launcherArgs[1:], url)
+	args := append(launcherArgs, url)
 	cmd := exec.Command(launcherExe, args...)
 	cmd.Stdout = b.stdout
 	cmd.Stderr = b.stderr
@@ -79,6 +75,32 @@ func (b *Browser) browse(url string, env []string) error {
 	return cmd.Run()
 }
 
+// splitLauncher resolves the launcher string to an executable path and
+// any extra arguments. Try the literal path first so launchers stored
+// in a directory with spaces, like
+// `C:\Program Files\Google\Chrome\Application\chrome.exe`, work without
+// the user having to quote them. Fall back to shell-style word
+// splitting when the literal lookup fails, since that's how launchers
+// with arguments (`firefox --private-window`) are conventionally
+// configured.
+func splitLauncher(launcher string) (string, []string, error) {
+	if exe, err := safeexec.LookPath(launcher); err == nil {
+		return exe, nil, nil
+	}
+	parts, err := shlex.Split(launcher)
+	if err != nil {
+		return "", nil, err
+	}
+	if len(parts) == 0 {
+		return "", nil, fmt.Errorf("empty launcher")
+	}
+	exe, err := safeexec.LookPath(parts[0])
+	if err != nil {
+		return "", nil, err
+	}
+	return exe, parts[1:], nil
+}
+
 func resolveLauncher() string {
 	if ghBrowser := os.Getenv("GH_BROWSER"); ghBrowser != "" {
 		return ghBrowser

pkg/browser/browser_test.go

@@ -203,6 +203,38 @@ func TestBrowse(t *testing.T) {
 	}
 }
 
+// Regression for #174: a launcher path containing a space (a common
+// case on Windows with `C:\Program Files\...\chrome.exe`) was being
+// shell-split into garbage by shlex. splitLauncher should try the
+// literal path first so it survives unquoted.
+func TestSplitLauncherPathWithSpaces(t *testing.T) {
+	dir := t.TempDir()
+	subdir := filepath.Join(dir, "with space")
+	require.NoError(t, os.MkdirAll(subdir, 0o755))
+
+	name := "fake-browser"
+	if runtime.GOOS == "windows" {
+		name += ".exe"
+	}
+	path := filepath.Join(subdir, name)
+	require.NoError(t, os.WriteFile(path, []byte("#!/bin/sh\n"), 0o755))
+
+	exe, args, err := splitLauncher(path)
+	require.NoError(t, err)
+	assert.Equal(t, path, exe)
+	assert.Empty(t, args)
+}
+
+// splitLauncher should still honor traditional `firefox --private`
+// style launchers that pass extra args alongside the binary name.
+func TestSplitLauncherWithArgs(t *testing.T) {
+	launcher := fmt.Sprintf("%q --private-window", os.Args[0])
+	exe, args, err := splitLauncher(launcher)
+	require.NoError(t, err)
+	assert.Contains(t, exe, filepath.Base(os.Args[0]))
+	assert.Equal(t, []string{"--private-window"}, args)
+}
+
 func TestResolveLauncher(t *testing.T) {
 	tests := []struct {
 		name         string